Sound recording device



Oct. 21, 1941. H. FLOOD. JR

SOUND RECORDING DEVICE Filed Feb. 21, 1940 2 Sheets-Sheet l ATTORNEZ'Y Oct. 21, 1941. H. FLOOD, JR

SOUND RECORDING DEVICE Filed Feb. 21, 1940 2 Sheets-Sheet 2 INVENTOR f/E/V/QY F2000, fir.

ATTORNEY Patented Oct. 21, 1941 NT OFFICE SOUND RECORDING DEVICE.

Henry Flood, Jr., Rahway, N. J., assignor to Recordgraph Corporation, New York, N. Y., a corporation of Delaware Application February 21, 1940, Serial No. 320,084

13 Claims.

This invention relates to recording machines and more particularly to recording machines in latter preferably .being in the form of a strip of film.

The object of the invention is to prevent damage to the record which might be caused by a lateral movement of the stylus across the record while engaged therewith.

In the recording mechanism to which this invention is applicable, a plurality of substantially parallel sound tracks are made on a film by means of a stylus. The recording head is mounting means whereby any undesired relative movement between the recording head and record medium is prevented. For instance, when the stylus is in engagement with the record medium, it is not desired that the stylus be moved laterally across the record as such movement would result in damaging the same.

In one form of the invention, the stylus and record medium are moved laterally to one another during recording, this movement being automatically brought about after the completion of one sound track. Manual means are also provided for moving the record and stylus relatively transversely in the opposite direction and means are provided to prevent such manual lateral movement unless the stylus is disengaged from the record medium.

Further features and advantages of the invenwhich a stylus records on a record medium, the

tion will better be understood by reference to the accompanying drawings in which several forms, which the invention may take, are shown. In said drawings Figure 1 is a perspective view partly in section showing a form in which the relative lateral movement between the recording head and record medium is entirely manual;

Figure 2 is a section of the line 2-2 Fig. 1 and shows the connection between the recording head positioning means and the lock;

Figure 3 is a perspective view of a different embodiment in which likewise the transverse movement is entirely manually controlled;

Figure 4 is a perspective view of a form in which transverse movement in one direction is brought about automatically. under control of the film with manual means for causing transverse movement in the opposite direction, with means for preventing transverse movement under manual control unless the recording head is in nonrecordingposition; and v Figure 5 is a section of the line 5-5 Fig. 4 and is a detail showing some of the parts of Fig. 4 in a difierent position.

Referring to Figure 1, the form of the invention here disclosed is applicable to the machine shown and described in Patent #2,173,048, September 12, 1939.

I represents the record medium which is in the form of a film. This may be moved longitudinally by means described in said patent or in any other well known manner. 2 represents the recording head and 3 the stylus. Extending rearwardly from the recording head is a tone arm 4 pivoted at 5 between two arms 6 projecting from a sleeve 8. The sleeve 8 is slidable on shaft 9 and is moved transversely of such shaft by means of a lever Ill pivoted at H. The pivot I] is supported by a sleeve l2 carried by a stationary part of the machine. The shaft 9 is carried by base members H; .The lever I0 is notched at its forward end and engages a pin I6 projecting from the sleeve 8. The rear end of the lever carries an upstanding portion [8 through which projects a spring pressed plunger is. This plunger is adapted to engage holes 20 in an arcuate plate 2|, each hole being spaced apart a distance such that when said lever is moved to align the plunger ill with successive holes, the recording head is moved from one sound track to the next. The lower end of the plunger! is provided with a notch, the function of which will be later pointed out. It will be noted that the lever I0 is pivoted near one end so that the movement of the rear end is greater than the movement of the recording head.

In the position of the parts shown in Figures 1 and 2, the stylus 3 is in engagement with the record medium. Under these conditions, it is desirable that the lever Ill be locked from operation so that it is not possible to move the stylusacross the record in either direction at this time.

This locking is accomplished by means of a slidable plate 22 formed in the shape of a sector and supported by an are shaped plate 23 carried by supports 24 which latter also support the armate plate 2|. In the position of the parts shown in Figure 2, the plate 22 is in engagement with and since it must be lifted in order to move the lever l8 about its pivot ii, the lever is thereby locked as well as the recording head.

Movement of the locking plate 22 is brought about through the medium of a slide 28 passing through the sleeve l2 and controlled by a cam 28 on the shaft 88, the forward end of the slide 28 engaging the cam 28 to hold the locking plate 22 in engagement with the notch in the plunger l8.

It is desirable to permit free manual movement of the recording head transversely of the record medium in order to position the stylus at different sound tracks. Since the recording stylus, however, might injure the. sound tracks already made in the record medium, it is desirable that the recording head and stylus be not moved across the record medium while the stylus is engaged therewith but only when the stylus is raised out of contact with the record medium. Therefore to prevent manual transverse movement while the stylus is in engagement with the record medium, the cam 28 is so shaped that when it is rotated clockwise from the position shown in Figures 1 and 2 through approximately 90, the high part of the cam releases the slide 28 which is retracted by a spring 82 thereby releasing the lock. -At the same time a high portion of said cam 28 engages the underside of the plate 4 and lifts the recording head so that the stylus is out of engagement with the record medium. A knurled knob 84 at the outer end of shaft 88 enbales it to be turned to position the recording head in a recording position or in a non-recording position and to control the lock. The movement of the head to non-recording position is effected by positive action of the cam 28. The movement to recording position is. however, brought about by gravity when the cam 28 is in the position shown in the drawings.

By the mechanism so far described, manual means are provided for moving the recording head transversely of the record medium and the plate 22 provides means for preventing such transverse movement when the recording head is in recording position.

The construction shown in Figure 3 accomplishes the same purpose as the construction shown in Figures 1 and 2 but the means for moving the recording head transversely of the record medium is somewhat different as is also the speciflc form of locking means.

As in the Figure 1 construction, the recording head isprovided with a rearwardly projecting tone arm 4 which is pivoted at 5 to two arms 8 extending rearwardly from the sleeve 8. The sleeve 8 is internally threaded and a shaft 8 is provided with a threaded portion l8 for engagement with the internal threads of the sleeve 8 whereby relative transverse movement between the recording head and record medium is brought about. The shaft 8 is provided at one end with a knurled knob 88 and is suitably supported in base members l4. At its opposite end it carries 88 is adapted to be acted upon by a cam 48 carried by shaft 88 which shaft is suitably supported in the base members i4. Shaft 88 also carries another cam 82 which is adapted to engage the underside of the tone arm 4 in any lateral position of the latter to thereby move the recording head out of recording position. The cams 48 and 82 are so shaped that when the shaft 88 is moved from the position shown in Figure 8 in a counterclockwise direction through approximately 90, the recording head is lifted to a non-recording position and the cam 48 bearing upon the tail of the pawl 88 moves said pawl against the action of the spring 4! so that its tooth 44 is free of the notched wheel 88 thereby permitting the recording head to be moved under manual control of the knurled knob 88. When the parts, however, are in the position shown in Figure 3 with the recording head in recording position, the wheel 88 is locked against rotation and likewise the shaft 8. l a

In the constructions heretofore described the recording head is moved laterally entirely through manual control. The record groove in the forms shown consists of substantially parallel sound tracks and the positioning of the stylusin one or the other of said tracks is brought about either through movement of the lever I8 as in the Figures l and 2'constructions or by the knob 88 in the Figure 3 construction.

In the form of the invention shown in Figure 4, the relative transverse movement between the recording head and the record medium is brought about automatically under control of the record medium. Manual means are also provided for effecting such relative transverse movement. Normally when the recording head is in recording position both the automatic means and the manual means, for effecting transverse movement, are ineffective. When transverse movement is to be brought about automatically, the lock which normally prevents such movement is automatically released while the lock for preventing transverse movement by the manual means remains effective. Manual means are also provided for controlling the recording or non-recording position of the recording head and when this means is operated to move the recording head so that the stylus is a notched wheel 88 with which engages a pawl 88 pivoted at 48. A spring 4| connected at 42 to a stationary portion of the machine, tends to rock the pawl 38 about its pivot 48 to thereby cause its tooth 44 to engage a notch in the tooth out of contact with the recording medium, the lock which normally prevents transverse movement under manual control, is released.

The particular mechanism whereby the above results are accomplished, is illustrated in Figure 4, which is a perspective view more or less diagrammatic, however.

In this form of the invention, the film I is a continuous him, that is to say it is in the form of a single loop, or it may be taken of! from the 'inside of a reel and rewound upon the outside of the same reel. This type of continuous film support is well known in the art and is therefore not specifically shown.' It is illustrated in the patent to De Forest, 1,365,237, January 11, 1921. The recording head is shown at 2 and the stylus at 8. Rigidly connected to the recording head is a tone arm 4 having a portion 8 extending at right angles thereto, the portion 8 being pivotally carried by arms 8 projecting rearwardly from the sleeve 8. Projecting downwardly from the tone arm 4 is a pin l8- carrying a bar l2 at right angles thereto forming a T. Base members i4 support a shaft i8"- carrying a cam I8 which is adapted to engage the bar 12 to move the recording head from the position shown in Figure 4 which is the recording position, to the position shown in Figure which is the non-recording position. The bar i2- is of such length that the cam i8 may engage. it in any lateral position of the recording head and the pin ll acts as a stop to limit the rotation of the cam in one direction as shown in'Figure 4. t

The sleeve 8 is internally threaded for engagement with threads I9 formed on a shaft 20' also supported in the base members l4. The shafts 16' and 20' carry knurled knobs 2|- and 22', by which these shafts may be manually rotated.

If there were nothing to prevent such motion, turning of the knob 22 would result in moving the recording head transversely of the .record medium through means of the screw threads 19, sleeve 0 and connections to the port. With the pawl 25 in engagementwith the a ratchet 24, the shaft is locked by the pawl 1 against movement in a clockwise direction but said pawl does not lock it against movement in an anti-clockwise directiom It is however, normally locked from movement in an anticlockwise direction by other means associated with the automatic transversefeeding means, which means will now be described.

It will be noted that the screw threads I! are such that when the shaft 20' is turned in an anti-clockwise direction, the recording head is moved transversely of the film from left to right as shown in Figure 4 and indicated by the arrow A. As noted above the pawl 25 does not interfere with such anti-clockwise movement.

Such movement of the shaft 20" is preferably accomplished by a motor 28', the shaft 30" of which is connected to the shaft 2|! through means of a friction clutch ii. The motor is normally stationary and as noted above the shaft 2|! is normally locked against anti-clockwise movement. This movement is prevented by a ratchet wheel 32* secured to the shaft 20' adjae cent the ratchet 245. The teeth of the ratchets 24 and 32 face in the opposite direction and a pawl 33 is provided with a nose 34' which engages the ratchet 32 and holds it and the shaft 20 against anti-clockwise movement. Thus under the conditions shown in Figure 4, no transverse movement of the recording head relative to the recording medium can take place.

.When automatic transverse movement is to be brought about, however, the pawl 33" is released and a circuit is established through the motor under control of the record medium.

It has been stated that the film is a continuous one and therefore it is desirable that the recording head he moved transversely upon completion of each sound track. To this end an electrically conducting member 35 extends a suitable distance on both surfaces of the film. When this contact passes between the conducting rollers 36 a circuit is closed which may be traced as follows: From the negative temiinal 38 current passes along conductor 39' to junction 40 thence to conductor 4i which is in electrical contact with the lower conducting roller 36*, since at this time the conducting por- The current then passes along conductor 42 to a relay 43 through said relay to conductor 44-,

when thus energized moves its armature 48 to r close a contact at 50 to energize the solenoid 52". The circuit now established by the relay 43 may be traced as follows: From the terminal 38' along conductors l8 and BI to solenoid 52", through said solenoid, along conductor 53 to contact 50', thence through armature 48' to conductor 41-, to junction 45 and through conductor 46 back to the positive terminal 48.

While relay 43 is such as to operate upon a very small current, solenoid 52" is capable of carrying a sufficiently large current to operate pawl 33' to lift its nose out of engagement with a tooth of the ratchet 32. The pawl 23 is pivoted intermediate its ends at 54 and is urged to ratchet engaging position by .a spring 56. The pawl 33' at its left hand end, as shown in Figure 4, carries a contact 51 which when the pawl is lifted, makes contact with an electrical conducting member' 58 to close a circuit through the motor, the circuit taking the following path: From the negative terminal 38 along conductor 39* to conductor ii to Junction 59, along conductor 60 to the motor. Afterpassing through the motor the current leaves by conductor 6i which is connected to conducting member 58, thence through contact 51 to conductor 62 which is connected to condutor 46*, the latter passing to the positive terminal 48'. As soon as the motor starts to move the shoulder of the tooth on the rathet 32 passes beneath the nose 34 of the pawl 33' and holds the contact between 51 and 58 closed. In the meantime the electrically conducting member 35 has passed beyond the contact rollers 36 and the circuits through the relay 43'- and the solenoid 52 are broken. The motor circuit, however, is still maintained by reason of the pawl 33 riding upon the periphery of a ratchet tooth of the ratchet 32'. When the shaft 20"- has been turned a distance between one ratchet tooth and the next, the pawl 33 under influence of its'spring 56 drops behind the shoulder formed by the adjacent tooth and positively stops the shaft 20 at a definite point which in the present instance corresponds to the location of the stylus at the next sound track. Although the motor circuit is broken as soon as the pawl 33' has seated itself in the next adjacent notch of the wheel 32, its momentum causes it to drift somewhat, after its source of power is cut oil. This overrunning oi the motor is taken care of by slippage of the frictional clutch 3|.

The mechanism Just described for automatically causing relative transverse movement between the record medium and the recording'head is not claimed per se in the present application but only in combination with mechanism now to be described whereby the locking pawl 25 is controlled. 1

It has been previously described how the knob 2i connected to the shaft l6 through the medium of the cam i8 positions the recording tion 35 of the film bridges the two rollers 36*. the shaft It carries the roller 64 having a segwhat less than 360, the cam i8 engaging the T- -bar l2raises the recording head which then assumes the position shown in Figure During the early part of this movement the electrically. conducting segment 85 bridges contacts 58 and 10 which has no effect tmchangethe position of any of the parts as will later 'be made clear.

As theshaft l5 continues to rotate, however, in an anti-clockwise direction, the segment 55 bridges contacts 12 and I4 and then passes to the position shown in full lines in Figure 5. The bridging of contacts 12 and" results in energizing solenoid 15 which acts on'the tail of the pawl 25 and lifts its noseout of Q engagement with a [tooth of the ratchet 24', The pawl is held inthi s' position by a spring clip 11 with which the tail of the pawl contacts. The'pawi is thus heldin its disengaged position'even though segment 58 has passed the position shown in Figure 5 and thereby broken the contactbetween 12 and I4. The circuit established through contacts 12 and 14 may be traced as follows: From the negative terminal 38" to junction 18 thence along conductor 18 to junction 80, along conductor 8i to contacts 12 and I8, thence along conductor 82 to solenoid 1.5, thence by way of conductors 83 and 85 to junction 88 which connects to the conductor 46 leading to the positive side of the line at 48. Thus manipulation of the knob 2| serves to position the recording head in non-recording position and to lift the pawl 25 from engagement with the ratchet 24 thereby permitting the shaft to be rotated by manipulation of the knob 22" to move the stylus across the film from right to left.

When the knob 2| is turned from the position shown in Figure 5 to the position shown in Figure 4 by a clockwise movement, the segment 56 first sweeps by contacts 12 and H which results in again closing the circuit through solenoid 18. This, however, has no effect because the pawl is already in the position to which such solenoid would have moved it. As the shaft [8 with the drum 84 continues its movement, segment bridges contacts 58 and Ill thereby establishing a circuit through solenoid 88 which immediately disengages the pawl25 from the clip 11 so that it may engage a shoulder on the ratchet 2A. The pawl 25 is shown somewhat out of proportion in Figure 4 which as previously stated is a more or less diagrammatic perspective representation. In practice that portion of the pawl 25 extending to the right of its pivot 25 is heavier than its tail end so that when the solenoid 88 releases the pawl from the clip 11, it remains in engagement with the ratchet until moved out of engagement by a subsequent energization of the solenoid 18. A light spring 90 may obviously be provided to hold the pawl into engagement with the ratchet, such spring being of such tension that it may readily be overcome by the solenoid I6.

The circuit which is established by the closing of the contacts 68 and 10 m y e traced as follows: From the terminal 58 alon colldlmtol 58 to junction I8, thence through conductor 18 to contacts 18 and 58, from 58 the current passes through conductor 8! to solenoid 58, through said solenoid to conductor 82 to junction 85, thence through conductor 85 to junction 85 and back to the positive terminal 58.

From theforegoing it will be obvious that under normal conditions, with the circuit at contacts 85' open, no movement of the shaft 25" in either direction can take place and hence no transverse movement of the recording head. When, however, the film which is moving in the direction of the arrow B, Figure 4, causes 85 to bridge contacts 55*, the pawl llunlocks ratchet 52 and permits the motor through the shaft 25" to move the recording head from one sound track to the next. Since this motion of shaft 25, is in an anti-clockwise direction, the pawl 25, even though it is in engagement with the ratchet 24', does not prevent this movementsince its nose rides upon the ratchet tooth and falls into the next adjacent notch whenthe recording head has completed one step of transverse movement. It is to be noted, however, that the raising of the pawl 25 by the ratchet 24 is small in comparison to the distance said pawl'is raised by the solenoid l5 and therefore when raised by the ratchet the tail of the pawl does not contact the clip l'l, so that thepawl 25 serves to lock the shaft 25 against movement in a clockwise direction after each transverse step of movement of the recording head, brought about through the automatic means.

When the recording head is raised to non-recording position by manipulation of the knob 2|, however, the pawl 25 is raised and held by the clip TI and the knob 22* may then be manipulated to move the recording head across the film from right to left. It cannot be moved, however, from left to right because the pawl 85 prevents such motion.

Variations may be resorted to within the scope of the invention without departing from the spirit thereof.

What I claim is:

1, In a sound recording device including a recording head and a record medium, a stylus carried by the head for recording on the record medium, means operatively related to said head for positioning said head in a recording position and in a non-recording position, manual means operatively related to said head for moving the recording head transversely of the record medium and means controlled by said head positioning means for preventing transverse motion of said recording head by said manual means.

2. In a sound recording device including a recording head and a record medium, a stylus carried by the head for recording on the record medium, means operatively relatedto said head for moving said head transversely of the record medium, a lock for preventing said transverse movement, means operatively related to said head for positioning said head in a recording position or in a non-recording position and concomitantly controlling the effectiveness and ineflectiveness of said lock.

3. In a sound recording device including a recording head and a record medium, a stylus carried by the head for recording on the record medium, manual means operatively related to said head for moving said head transversely of the record medium, a lock operable to prevent or permit such transverse movement, and manual means operatively related to said head to move the recording head out of recording position and concomitantly render said lock ineffective to prevent transverse movement.

4. In a sound recording device including a recording head and a record medium, a stylus car-' ried by. the head for recording on the record me-' dium, said head positionable in a recording position and in a non-recording position, manual means operatively related to said head for causing relative transverse movement between said recording head and record medium, manual means operatively related to said head for posi-- tioning the recording head in recording position or non-recording position, and a lockior preventing said relative transverse movement under control of said head positioning means.

5. In a'sound recording device including a recording head and a record medium, a stylus carried by the head for recording on the record meposition, a lock for preventing said relative transverse movement, and means controlled by said head positioning means formoving said lock to unlocking position.

6. In a sound recording device including a recording head and a record medium, a stylus carried by the head for'recording on the record medium, said head positionable in a recording position and in a non-recording position, a shaft, a cam on said shaft, connections from said cam to said head for moving said head to a non-recording position and permitting said head to move under gravity to a recording position according to the position of said cam, means for causing relative transverse movement of said head and medium, a lock for preventing such movement,

a and a second cam on said shaft for controlling said lock.

7. In a sound recording device including a recording head and a record medium, a stylus carried by the head for recording on the record medium, said head positionable in a recording position and in a non-recording position, a shaft, a cam on ,said shaft, connections from said cam to said head for moving said'head toa non-recording position and permitting said head to move under gravity to a recording position according to the position of said cam, means for causing relative transverse movementof said head and medium, a lock for preventingsuch movement, and a connection between said cam and lock whereby when said lock is eflective said head is in recording position and when said recording head is in non-recording position said lock is ineffective.

1 8. In a sound recording device, including a recording head and a record medium said head positionabie in a recording position and a non-recording position in respect of said medium. means for causing relative transverse movement between said recording head and record medium means controlling the position oi. said recording head in recording or non-recording position, and

means normally rendering said transverse moving means ineflfe'ctive when the recording head is in recording position.

9. In a sound recording device, including a recording head and a record medium, manual means and motor means for causing relative movement between said recording head and record medium, means normally preventing transverse movement in either direction, means operatively related to said head for positioning said head in a recording position or in a nonrecording position, said latter means rendering one of said locks ineffective.

- '10. In a sound recording device including a recording head and a record medium, manual means for causing relative. transverse movement between said recording head and record medium,

in one direction, motor means for causing relative transverse movement between said recording head and record medium in the opposite direction, means for normally preventing such transverse movement in either direction, means operatively related to said head for positioning said recording head in a recording position and in a non-recording position, and means under control of said last mentioned means for controlling the effectiveness or ineffectiveness or said manual means to permit or prevent the same from causing transverse movement.

11. In a sound recording device including a recording head and a record medium, means for moving said head and mediumrelatively, transversely, in one direction, means controlled by the record medium for causing said relative movement, manual means for causing said relative movement in the opposite direction, means normally preventing such movement, means operatively related to said head for positioning the head in a recording position and in a non-recording position, and means for releasing said' lateral movement preventing means under control of said positioning means.

12. In a sound recording device including a recording head and a record medium, means for moving said head and medium relatively, transverse'ly, in one direction, means normally preventing such movement, means controlled by the record medium for causing said relative 1 movement, and releasing said preventing means, manual means for causing said relative -movement in the opposite direction, means normally preventing such movement, means operatively related to said head for positioning the headina recording position and in a non-recording position, and means. for releasing said last mentioned lateral movement preventingmeans, un-

13. In a sound recording-device including a stylus and a strip of film on whictthe'mtylus records a plurality 01' parallel sound tracks, automatic means operatively related to said stylus for moving the stylus' from one, sound track-to the next adjacent track while the stylus'continues to record, means normally 'Iocking'thet' stylus irom any transverse movement in either direction, and meansyun'der control of the film.

for rendering the locking means ineffective to permit the automatic means to move the stylus from one track to the next-in one direction. --rmnRY'm.oop,,-In., 

